How to Grow Zinnia (short season varieties) in Alaska

Growing zinnias in Alaska can be a rewarding experience, especially if you choose the right varieties for the short growing season. Known for their vibrant colors and ability to attract pollinators, zinnias are a favorite among gardeners. This article will guide you through the process of growing short season zinnia varieties in the unique climate of Alaska.

Understanding Zinnia Varieties

Zinnias belong to the Asteraceae family and are native to Mexico and the southwestern United States. They are annual flowers that come in various species, but when it comes to short growing seasons like those in Alaska, certain varieties are better suited for success.

When selecting zinnia seeds, look for:

Short-season varieties: These typically mature faster and can bloom within 50-70 days after sowing.
Dwarf or compact varieties: These plants are easier to manage in smaller spaces and often have a shorter stature.
Disease-resistant hybrids: Resistance to powdery mildew and other diseases is crucial for growing healthy plants.

Recommended Short Season Varieties

Zinnia elegans ‘State Fair’
Maturity: 60 days
Height: Up to 3 feet
Features: Large blooms in various colors.
Zinnia elegans ‘Profusion’
Maturity: 50-60 days
Height: 12-18 inches
Features: Compact growth with good disease resistance.
Zinnia angustifolia ‘Crystal White’
Maturity: 50-60 days
Height: 12-18 inches
Features: Outstanding white blooms that are drought tolerant.
Zinnia ‘Cut and Come Again’
Maturity: 60 days
Height: 24-30 inches
Features: Continuous blooming throughout the summer with vibrant colors.

Preparing for Planting

Choosing the Right Location

Zinnias thrive in full sun, so select a location that receives at least six to eight hours of direct sunlight daily. A south-facing garden bed is ideal as it maximizes sunlight exposure. Additionally, ensure the site has good air circulation to help prevent fungal diseases.

Soil Preparation

Zinnias prefer well-draining soil with a pH between 6.0 and 7.0. Here’s how to prepare your soil:

Test Soil pH: Use a soil test kit to determine your soil’s pH level.
Amend Soil: If needed, amend your soil with lime (to raise pH) or sulfur (to lower pH).
Add Organic Matter: Incorporate compost or well-rotted manure into the soil to improve fertility and drainage.
Tillage: Loosen the soil with a tiller or garden fork to break up compacted areas.

Timing Your Planting

In Alaska, the last frost date can vary significantly by region; typically, it’s around late May to early June. To ensure successful germination and growth:

Start seeds indoors 4-6 weeks before the last frost date if you want an early start.
Direct sow seeds outdoors after the danger of frost has passed.

Planting Zinnias

Starting Indoors

If starting indoors:

Containers: Use seed trays or peat pots filled with seed-starting mix.
Sowing Seeds: Plant seeds about ¼ inch deep and water gently.
Light Requirements: Place under grow lights or in a sunny window.
Thinning Seedlings: Once seedlings have two sets of true leaves, thin them out so they are spaced about 2 inches apart.

Direct Sowing Outdoors

For direct sowing:

Row Spacing: Create rows spaced about 12 inches apart.
Sowing Seeds: Plant seeds about ¼ inch deep and water lightly.
Watering Regime: Water regularly, making sure not to over-saturate the soil.

Care and Maintenance

Watering

Zinnias prefer evenly moist soil but do not like soggy conditions. Water deeply once a week during dry spells while avoiding water on foliage to reduce disease risk.

Fertilization

Use a balanced fertilizer at planting time and follow up with another application mid-season:

Application Rate: Follow package directions for dosage.
Organic Options: If you prefer organic gardening, consider using compost tea or fish emulsion.

Pruning and Deadheading

To encourage continuous blooming:

Remove spent flowers (deadheading) regularly.
For taller varieties, pinch back tips occasionally to promote bushier growth.

Pest Management

Common pests affecting zinnias include aphids, spider mites, and whiteflies. To manage these pests:

Natural Predators: Introduce ladybugs or lacewings which feed on aphids.
Insecticidal Soap: Use insecticidal soap sprays if infestations become severe.
Regular Inspection: Check plants frequently for signs of pest activity or distress.

Dealing with Weather Challenges

Alaska’s unique weather can present challenges when growing zinnias:

Frost Protection

Be prepared for late frosts by having row covers or cloches ready:

Cover plants if temperatures drop unexpectedly late in spring.

Wind Protection

Strong winds can damage tall zinna varieties:

Choose sheltered locations for planting or use windbreaks like fences or hedges.

Harvesting Flowers

Zinnias make excellent cut flowers! To harvest:

Choose blooms that are fully open but not yet wilting.
Cut stems early in the morning for optimal freshness.
Place cut flowers immediately in water to prolong their vase life.

Conclusion

Growing short season zinnias in Alaska presents unique challenges, but with careful planning and attention to detail, gardeners can enjoy beautiful blooms throughout the summer months. By selecting suitable varieties, preparing your garden properly, providing adequate care, and taking precautions against pests and weather extremes, your zinnia experience can be both fruitful and visually stunning! With vibrant colors adorning your garden, you’ll create an inviting space that attracts pollinators and brightens your outdoor environment all summer long!